Status of the midwifery workforce and childbirth services and the impact of midwife staffing on birth outcomes in China: a multicentre cross-sectional study.

OBJECTIVE: To investigate the status of the midwifery workforce and childbirth services in China and to identify the association between midwife staffing and childbirth outcomes. DESIGN: A descriptive, multicentre cross-sectional survey. SETTING: Maternity hospitals from the eastern, central and western regions of China. PARTICIPANTS: Stratified sampling of maternity hospitals between 1 July and 31 December 2021.The sample hospitals received a package of questionnaires, and the head midwives from the participating hospitals were invited to fill in the questionnaires. RESULTS: A total of 180 hospitals were selected and investigated, staffed with 4159 midwives, 412 obstetric nurses and 1007 obstetricians at the labour and delivery units. The average efficiency index of annual midwifery services was 272 deliveries per midwife. In the sample hospitals, 44.9% of women had a caesarean delivery and 21.4% had an episiotomy. Improved midwife staffing was associated with reduced rates of instrumental vaginal delivery (adjusted ß -0.032, 95% CI -0.115 to -0.012, p<0.05) and episiotomy (adjusted ß -0.171, 95% CI -0.190 to -0.056, p<0.001). CONCLUSION: The rates of childbirth interventions including the overall caesarean section in China and the episiotomy rate, especially in the central region, remain relatively high. Improved midwife staffing was associated with reduced rates of instrumental vaginal delivery and episiotomy, indicating that further investments in the midwifery workforce could produce better childbirth outcomes.

Assessing women's and health professionals' views on developing a midwifery-led mobile health app intervention in pregnancy: A descriptive qualitative study.

AIMS: To explore women's and health professionals' views on the development of a midwifery-led mHealth app intervention in antenatal care and their demands for app functionality. DESIGN: Descriptive qualitative research was utilized. METHODS: In total, 15 pregnant or postpartum women were interviewed via in-depth interviews and 10 health professionals including obstetricians, midwives and obstetric nurses were invited to participate in a focus group discussion (FGD). All interviews and the FGD were analysed using qualitative content analysis. RESULTS: Four key themes emerged from the data, including (1) limitations of current maternity care services; (2) potential benefits for mHealth app-based midwifery care; (3) possible challenges for providing midwifery care through mHealth apps and (4) suggestions and needs for developing a midwifery-led mHealth app. Participants agreed on the potential need of developing a midwifery-led mHealth app in antenatal care to increase access to midwifery care services and to meet women's diverse needs. Participants preferred to develop professional, reliable, full-featured and interactive mobile applications. The main functions of midwifery-led mHealth apps included personalized assessment and health education, self-monitoring and feedback, data sharing and interactive functions. Women mentioned that online communication and consultation with midwives could help them receive continuous support outside facilities. Health professionals expressed it would be of great convenience and timeliness to send personalized messages to women and to inform them of healthy lifestyles during pregnancy. The challenges included a shortage of human resources, medico-legal risks associated with mHealth and data security risks. CONCLUSIONS: This study explores the individual views and functional needs of target users and healthcare providers for developing a midwifery-led mHealth app in antenatal care, which will serve as a reference for future application development. IMPACT: Our study has important and practical implications for guiding the development of future midwifery-led mHealth app interventions. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Unraveling Anisotropic and Pulsating Etching of ZnO Nanorods in Hydrochloric Acid via Correlative Electron Microscopy.

Despite much technical progress achieved so far, the exact surface and shape evolution during wet chemical etching is less unraveled, especially in ionically bonded ceramics. Herein, by using in situ liquid cell transmission electron microscopy, a repeated two-stage anisotropic and pulsating periodic etching dynamic is discovered during the pencil shape evolution of a single crystal ZnO nanorod in aqueous hydrochloric acid. Specifically, the nanopencil tip shrinks at a slower rate along [0001̅] than that along the ⟨101̅0⟩ directions, resulting in a sharper ZnO pencil tip. Afterward, rapid tip dissolution happens due to accelerated etching rates along various crystal directions. Concurrently, the vicinal base region of the original nanopencil tip emerges as a new tip followed by the repeated sequence of tip shrinking and removal. The high-index surfaces, such as {101̅m} (m = 0, 1, 2, or 3) and {21̅ 1̅n} (n = 0, 1, 2, or 3), are found to preferentially expose in different ratios. Our 3D electron tomography, convergent beam electron diffraction, middle-angle bright-field STEM, and XPS results indicate the dissociative Cl- species were bound to the Zn-terminated tip surfaces. Furthermore, DFT calculation suggests the preferential Cl- passivation over the {101̅1} and (0001) surfaces of lower energy than others, leading to preferential surface exposures and the oscillatory variation of different facet etching rates. The boosted reactivity due to high-index nanoscale surface exposures is confirmed by comparatively enhanced chemical sensing and CO2 hydrogenation activity. These findings provide an in-depth understanding of anisotropic wet chemical etching of ionic nanocrystals and offer a design strategy for advanced functional materials.

The effects of a midwife-led weight management program for pregnant women: A randomized controlled trial.

BACKGROUND: Inappropriate weight gain during pregnancy may present risks for maternal and newborn health. Pregnancy is considered the optimal time to intervene on women's health behaviors such as eating habits and physical activity. However, current clinical practice guidelines for weight management during pregnancy were not fully based on randomized trials, thus lacking specific "active intervention ingredients" that are proven effective in achieving appropriate gestational weight gain. Therefore it is essential to develop and implement an evidence-based weight management program for pregnant women. OBJECTIVE: To examine the effects of a midwife-led weight management program on improving appropriate gestational weight gain, health literacy, experience of antenatal care, and maternal and neonatal outcomes among Chinese pregnant women. DESIGN: A two-group randomized controlled trial. SETTINGS AND PARTICIPANTS: A total of 426 pregnant women were recruited from a tertiary women's hospital in eastern China. METHODS: Participants were randomly allocated to either intervention group (n = 213) or control group (n = 213). Women in the intervention group participated in a midwife-led weight management program during pregnancy, while women in the control group received the conventional obstetrician-led antenatal care. We assessed women at the first antenatal contact, 35-36 weeks gestation and 2-3 days postpartum. Data on gestational weight gain, health literacy, experience of antenatal care, and maternal and neonatal outcomes were compared between the two groups. Dummy variable analysis was conducted to reveal the effect of weight management program on gestational weight gain. RESULTS: The overall gestational weight gain between the two groups was not statistically different (t = -1.377, P = 0.170). Compared with women in the control group, the odds of having inappropriate gestational weight gain was lower in the intervention group (OR = 0.270, 95%CI 0.169, 0.431). Further subgroup analyses showed that women in the intervention group had lower risk of inadequate gestational weight gain (OR = 0.305, 95%CI 0.180, 0.515) and excessive gestational weight gain (OR = 0.236, 95%CI 0.138, 0.404) than those in the control group. The score of experience of antenatal care was significantly higher in the midwife-led weight management group than that in the control group (193.70 ±â€¯18.51 versus 165.70 ±â€¯28.23, P < 0.001). Women's health literacy score was higher in the intervention group than control group [74.41 (69.57, 81.77) versus 71.88 (66.23, 77.18), P = 0.004]. CONCLUSION: Compared with the conventional antenatal care, the midwife-led weight management program could facilitate appropriate gestational weight gain, enhance health literacy, and promote positive experience of antenatal care for Chinese pregnant women.

Associations between pro-inflammatory cytokines and fatigue in pregnant women.

Background: Fatigue is one of the most prevalent symptoms among pregnant women. In patients with various diseases, pro-inflammatory cytokines are associated with fatigue; however, such associations are unknown in pregnant women. Objectives: The objective of this study was to examine the associations between pro-inflammatory cytokines and prenatal fatigue. Methods: A cross-sectional study was conducted on 271 pregnant Chinese women in their third trimester of pregnancy. Patient-reported Outcome Measurement Information System (PROMIS) was used to evaluate women's prenatal fatigue. Using enzyme-linked immunosorbent assay (ELISA), the serum concentrations of four pro-inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1ß), interleukin 6 (IL-6) and interleukin 8 (IL-8), were measured. The data was analyzed by correlation analysis and general linear regression analysis. Results: In this sample, the mean (standard deviation) of fatigue scores was 51.94 (10.79). TNF-α (r = 0.21, p < 0.001), IL-6 (r = 0.134, p = 0.027) and IL-8 (r = 0.209, p = 0.001) were positively correlated to prenatal fatigue, although IL-1ß was not. TNF-α (ß = 0.263, p < 0.001), along with sleep quality (ß = 0.27, p < 0.001) and depression (ß = 0.376, p < 0.001) independently predicted prenatal fatigue. Conclusions: TNF-α was identified as an independent biomarker for prenatal fatigue in our study. Reducing pro-inflammatory cytokines may be a unique method for lowering prenatal fatigue and, consequently, enhancing mother and child health.

Defect Engineering in Thickness-Controlled Bi2O2Se-Based Transistors by Argon Plasma Treatment.

We present a simple, effective, and controllable method to uniformly thin down the thickness of as-exfoliated two-dimensional Bi2O2Se nanoflakes using Ar+ plasma treatment. Atomic force microscopy (AFM) images and Raman spectra indicate that the surface morphology and crystalline quality of etched Bi2O2Se nanoflakes remain almost unaffected. X-ray photoelectron spectra (XPS) indicate that the O and Se vacancies created during Ar+ plasma etching on the top surface of Bi2O2Se nanoflakes are passivated by forming an ultrathin oxide layer with UV O3 treatment. Moreover, a bottom-gate Bi2O2Se-based field-effect transistor (FET) was constructed to research the effect of thicknesses and defects on electronic properties. The on-current/off-current (Ion/Ioff) ratio of the Bi2O2Se FET increases with decreasing Bi2O2Se thickness and is further improved by UV O3 treatment. Eventually, the thickness-controlled Bi2O2Se FET achieves a high Ion/Ioff ratio of 6.0 × 104 and a high field-effect mobility of 5.7 cm2 V-1 s-1. Specifically, the variation trend of the Ion/Ioff ratio and the electronic transport properties for the bottom-gate Bi2O2Se-based FET are well described by a parallel resistor model (including bulk, channel, and defect resistance). Furthermore, the Ids-Vgs hysteresis and its inversion with UV irradiation were observed. The pulsed gate and drain voltage measurements were used to extract trap time constants and analyze the formation mechanism of different hysteresis. Before UV irradiation, the origin of clockwise hysteresis is attributed to the charge trapping/detrapping of defects at the Bi2O2Se/SiO2 interface and in the Bi2O2Se bulk. After UV irradiation, the large anticlockwise hysteresis is mainly due to the tunneling between deep-level oxygen defects in SiO2 and p++-Si gate, which implies the potential in nonvolatile memory.

FEDResNet: a flexible image encryption and decryption scheme based on end-to-end image diffusion with dilated ResNet.

Image encryption has emerged as a method of disguising an image with a noisy or meaningless appearance to prevent its content from being accessed by unauthorized users. We propose an architecture named flexible image encryption and decryption ResNet (FEDResNet) for diffusing an image in end-to-end mode. The architecture consists of an encryption network for diffusing the image and a decryption network for restoring the plaintext image from the diffused image. To enhance the security of the encrypted image, the diffused image is further processed with two optional operations: parallel scrambling and serial diffusion. Two key planes are constructed based on a user-defined key with a chaotic map to control the authority to access images. The structure and parameters of FEDResNet can be shared publicly by different users; hence, it is more flexible and convenient than previous deep-learning-based image encryption methods. A classification network is trained to classify medical images in ciphertext environments. The proposed FEDResNet is trained and tested on the ImageNet data set. Extensive experiments have been performed, and the experimental results suggest that the proposed model can achieve a high level of security with satisfactory efficiency. The experimental results also show that FEDResNet-encrypted images can be classified directly in the ciphertext domain by authorized users as accurately as plaintext images, which is a superior property that is not possessed by traditional image encryption methods.

Effect of 580 °C (20 h) Heat Treatment on Mechanical Properties of 25Cr2NiMo1V Rotor-Welded Joints of Oscillating Arc (MAG) Narrow Gap Thick Steel.

The thick plate narrow gap welding of 25Cr2NiMo1V rotor steel is achieved by metal active gas arc welding, in which the weld gap was 18.04-19.9 mm. After welding, the weldment was heat treated at 580 °C (20 h). The impact and tensile properties in the as-welded and heat-treated were studied. The results show that after heat treatment, the coarse carbides in the center of the weld were transformed into fine granular carbides distributed along the grain boundaries, and the quantity of carbide precipitates in the weld near the fusion line was reduced. The tensile fracture mode changed from a ductile fracture to a combination of brittle and ductile fractures, and the tensile strength of the weld metal changed from 605 MPa to 543 MPa. After heat-treated, the radiation zone of the weld center changed from a brittle fracture to a combination of brittle and ductile fractures, and the impact energy changed from 141 J to 183 J; the characteristics of the brittle fracture in the radial zone of the fusion line were more obvious, and the impact energy changed from 113 J to 95 J. Therefore, after heat treatment, the toughness of the welded metal was improved, without reducing the strength and hardness of the welded metal to a large extent.

Zero-bias mid-infrared graphene photodetectors with bulk photoresponse and calibration-free polarization detection.

Bulk photovoltaic effect (BPVE), featuring polarization-dependent uniform photoresponse at zero external bias, holds potential for exceeding the Shockley-Queisser limit in the efficiency of existing opto-electronic devices. However, the implementation of BPVE has been limited to the naturally existing materials with broken inversion symmetry, such as ferroelectrics, which suffer low efficiencies. Here, we propose metasurface-mediated graphene photodetectors with cascaded polarization-sensitive photoresponse under uniform illumination, mimicking an artificial BPVE. With the assistance of non-centrosymmetric metallic nanoantennas, the hot photocarriers in graphene gain a momentum upon their excitation and form a shift current which is nonlocal and directional. Thereafter, we demonstrate zero-bias uncooled mid-infrared photodetectors with three orders higher responsivity than conventional BPVE and a noise equivalent power of 0.12 nW Hz-1/2. Besides, we observe a vectorial photoresponse which allows us to detect the polarization angle of incident light with a single device. Our strategy opens up alternative possibilities for scalable, low-cost, multifunctional infrared photodetectors.

Pregnant women's clinical characteristics, intrapartum interventions, and duration of labour in urban China: a multi-center cross-sectional study.

BACKGROUND: There is an increasing global trend towards the widespread over-medicalisation of labour and childbirth. The present study aimed to investigate pregnant women's clinical characteristics, intrapartum interventions, duration of labour and its associated factors; and to compare the differences of these variables between nulliparas and multiparas in China. METHODS: A multi-center cross-sectional study was carried out in three tertiary hospitals of Fudan University in Shanghai, China. A total of 1523 participants were approched and assessed for eligibility. Data on women's sociodemographic characteristics, intrapartum interventions, and duration of labour were measured and collected. Kaplan-Meier survival analysis was performed to present the curves of total duration of labour by parity. After z-transformation of labour duration, multivariable linear regression was used to control for confounding and to identify independent associations between potential associated factors and the primary outcome of labour duration. RESULTS: Overall, 1209 eligible women agreed to participate and were investigated. Rates of different intrapartum interventions were 27.4% in use of amniotomy, 37.9% in use of oxytocin, 53.0% in continuous electronic fetal monitoring, and 52.9% in epidural use, respectively. The curve of total duration of labour was significantly different between nulliparas and multiparas (P < .001). Of the 1209 participants, 983 (81.3%) women eventually achieved successful vaginal birth while 226 (18.7%) women ended in intrapartum caesarean section. The median duration of total stage of labour was significantly longer in the nulliparous group [9.38 (6.33,14.10) hours] than that in the multiparous group [5.08 (3.00,7.83) hours] (P < .001). The following factors were independently associated with longer duration of total stage of labour: epidural analgesia (P < .001), primiparity (P < .001), continuous electronic fetal monitoring (P = .035), and increased birth weight (P = .005). CONCLUSIONS: Intrapartum medical interventions become common obstetric practices in urban China. Multifactorial variables independently associated with longer duration of labour were identified, including epidural analgesia, primiparity, continuous electronic fetal monitoring, and increased birth weight. Further research is required to validate these variables and to determine the modifiable factors for labour management. And models of care with lower intervention rates such as midwife-led models of care should be developed and implemented in China.

Correction to: Pregnant women's clinical characteristics, intrapartum interventions, and duration of labour in urban China: a multi-center cross-sectional study.

An amendment to this paper has been published and can be accessed via the original article.

Employing a Bifunctional Molybdate Precursor To Grow the Highly Crystalline MoS2 for High-Performance Field-Effect Transistors.

Growth of the large-sized and high-quality MoS2 single crystals for high-performance low-power electronic applications is an important step to pursue. Despite the significant improvement made in minimizing extrinsic MoS2 contact resistance based on interfacial engineering of the devices, the electron mobility of field-effect transistors (FETs) made of a synthetic monolayer MoS2 is yet far below the expected theoretical values, implying that the MoS2 crystal quality needs to be further improved. Here, we demonstrate the high-performance two-terminal MoS2 FETs with room-temperature electron mobility up to ∼90 cm2 V-1 s-1 based on the sulfurization growth of the bifunctional precursor, sodium molybdate dihydrate. This unique transition-metal precursor, serving as both the crystalline Mo source and seed promotor (sodium), could facilitate the lateral growth of the highly crystalline monolayer MoS2 crystals (edge length up to ∼260 µm). Substrate surface treatment with oxygen plasma prior to the deposition of the Mo precursor is fundamental to increase the wettability between the Mo source and the substrate, promoting the thinning and coalescence of the source clusters during the growth of large-sized MoS2 single crystals. The control of growth temperature is also an essential step to grow a strictly monolayer MoS2 crystal. A proof-of-concept for thermoelectric device integration utilizing monolayer MoS2 sheds light on its potential in low-voltage and self-powered electronics.

Waveguide-Integrated Black Phosphorus Photodetector for Mid-Infrared Applications.

Midinfrared (MIR), which covers numerous molecular vibrational fingerprints, has attracted enormous research interest due to its promising potential for label-free and damage-free sensing. Despite intense development efforts, the realization of waveguide-integrated on-chip sensing system has seen very limited success to date. The huge lattice mismatch between silicon and the commonly used detection materials such as HgCdTe, III-V, or II-VI compounds has been the key bottleneck that hinders their integration. Here, we realize an integration of silicon-on-insulator (SOI) waveguides with black phosphorus (BP) photodetectors. When operating near BP's cutoff wavelength where absorption is weak, the light-BP interaction is enhanced by exploiting the optical confinement in the Si waveguide and grating structure to overcome the limitation of absorption length constrained by the BP thickness. Devices with different BP crystal orientation and thickness are compared in terms of their responsivity and noise equivalent power (NEP). Spectral photoresponse from 3.68 to 4.03 µm was investigated. Additionally, power-dependent responsivity and gate-tunable photocurrent were also studied. At a bias of 1 V, the BP photodetector achieved a responsivity of 23 A/W at 3.68 µm and 2 A/W at 4 µm and a NEP less than 1 nW/Hz1/2 at room temperature. The integration of passive Si photonics and active BP photodetector is envisaged to offer a potential pathway toward the realization of integrated on-chip systems for MIR sensing applications.

Efficient and reliable surface charge transfer doping of black phosphorus via atomic layer deposited MgO toward high performance complementary circuits.

Black phosphorus (BP), a fast emerging 2D material, has shown great potential in future electronics and optoelectronics owing to its outstanding properties including sizable band gap and ambipolar transport characteristics. However, its hole conduction dominance, featured by a much larger hole mobility and the corresponding on-current than that of the electrons, renders the reliable modulation of its carrier type and density a key challenge, thereby hindering its application to complementary electronics. Here, we demonstrate an efficient and reliable n-type doping for BP transistors via surface functionalization by atomic layer deposited magnesium oxide (MgO) with favorable controllability. By optimizing the MgO thickness, an electron mobility of up to 95.5 cm2 V-1 s-1 is reached with a simultaneous significant suppression of hole conduction. Subsequently, a high-performance complementary logic inverter is demonstrated within a single BP flake, which operates well with a supply voltage as low as <0.5 V, outperforming reported BP inverters in terms of logic level match, power consumption and process feasibility. Our findings suggest that surface charge transfer doping via MgO can be used as a promising technique towards high performance BP-based functional nanoelectronics.

Low-Frequency Noise in Layered ReS2 Field Effect Transistors on HfO2 and Its Application for pH Sensing.

Layered rhenium disulfide (ReS2) field effect transistors (FETs), with thickness ranging from few to dozens of layers, are demonstrated on 20 nm thick HfO2/Si substrates. A small threshold voltage of -0.25 V, high on/off current ratio of up to ∼107, small subthreshold swing of 116 mV/dec, and electron carrier mobility of 6.02 cm2/V·s are obtained for the two-layer ReS2 FETs. Low-frequency noise characteristics in ReS2 FETs are analyzed for the first time, and it is found that the carrier number fluctuation mechanism well describes the flicker (1/f) noise of ReS2 FETs with different thicknesses. pH sensing using a two-layer ReS2 FET with HfO2 as a sensing oxide is then demonstrated with a voltage sensitivity of 54.8 mV/pH and a current sensitivity of 126. The noise characteristics of the ReS2 FET-based pH sensors are also examined, and a corresponding detection limit of 0.0132 pH is obtained. Our studies suggest the high potential of ReS2 for future low-power nanoelectronics and biosensor applications.

Improve the operational stability of the inverted organic solar cells using bilayer metal oxide structure.

Operational stability is a big obstacle for the application of inverted organic solar cells (OSCs), however, less talked about in the research reports. Due to photoinduced degradation of the metal oxide interlayer, which can cause shunts generation and degeneration in ZnO interlayer, a significant degradation of open circuit voltage (Voc) and fill factor (FF) has been observed by in situ periodic measurements of the device current density-voltage (J-V) curves with light illumination. By combining TiOx and ZnO to form bilayer structures on ITO, the photovoltaic performance is improved and the photoinduced degradation is reduced. It was found that the device based on ZnO/TiOx bilayer structure achieved better operational stability as compared to that with ZnO or TiOx interlayer.

Transposition of the Zorro2 retrotransposon is activated by miconazole in Candida albicans.

Zorro2 is a member of a non-long terminal repeat (LTR) retrotransposon family in Candida albicans, but as yet no clear evidence has been provided to establish either transcription or transposition activity for Zorro2. In this study, the relative expression changes of two open reading frames in Zorro2, ORF19.7274 and ORF19.7275, were examined in response to miconazole (MCZ), and were found to be increased by this treatment. As well, the copy number and the transcripts of Zorro2 in MCZ-induced resistant daughter strains were increased compared to the parental strain, indicating that transposition of Zorro2 occurred during long-term MCZ treatment. Intriguingly, the transcription activity of Zorro2 retrotransposons was significantly inhibited when the cells were treated with MCZ together with antioxidant N-acetyl-L-cysteine (NAC). As both the level of intracellular reactive oxygen species (ROS) and the expression of genes involving DNA repair activated by MCZ were reduced when combined with the treatment of NAC, we propose that the damage caused by accumulation of ROS under MCZ stress is a major reason for the transcription and transposition activation of the Zorro2 retrotransposon.